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Formatting video for local playback
Introduction
This document introduces the broader concepts of digital video multimedia, and the specific details of formatting
video for Sony Ericsson phones using local storage and playback. A practical example of the process is also
included.
People who may benefit from this document include:
• Content providers.
• Software developers.
• Operators and service providers.
The competence required to follow this document extends only to basic computer skills, as
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Formatting video for local playback W810 W810i, W810c, W810a W800 W800i, W800c W600 W600i W550 W550i, W550c W300 W300i, W300c Z610 Z610i Note: Other Sony Ericsson phones can support the same containers and compression codecs as the phones listed here, however the exact parameters needed to encode videos for those phones may differ. As such it is recommended to verify successful playback on those phones when creating video for them. Terminology Anti-aliasing \- The technique of minimizing aliasin
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Formatting video for local playback Sampling \- The act of taking a portion of one sound recording, the sample, and reusing it as an instrument or element of a new recording. Stereo Sound \- Audio consisting of two channels, left and right. Streaming \- A method for making audio, video and other multimedia available in near realtime, that is the user can begin to watch or hear the content of a downloaded media file after only a short delay. Previously it was necessary to download an entire file
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Formatting video for local playback MPEG \- Moving Picture Experts Group, develops standards for digital video and digital audio compression. The MPEG standards are an evolving series, each designed for a different purpose. MPG \- MPEG-1 file. OGG \- Ogg Vorbis Codec Compressed WAV File. An open source patent-free audio compression format. Vorbis files compress to a smaller size than MP3 files. PCM \- Pulse code modulation. A digital scheme for transmitting analog data. Using PCM, it is possible
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Formatting video for local playback Resolution Both visible and audible information are naturally analogue mediums. This analogue information must be sampled to be stored digitally. The number of samples dictates the resolution of the digital copy, with more samples improving the resolution and definition. Within the scope of this document and its purpose, there are only four digital sample resolutions that are relevant. The first is the visual resolution of the video stream, measured in pixels
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Formatting video for local playback Video codecs include MPEG-1 and MPEG-2 as used for DVDs, and the many extensions and implementations of MPEG-4 such as WMV9, H.264, DivX, and so on. Common audio codecs include MP3, OGG, AAC, WMA, and AMR. {*}Containers{*} The separate data streams are almost always multiplexed (also referred to as 'muxed') together into one file, facilitating delivery and playback of both video and audio stream as a single object. The data streams are packaged in what is call
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Formatting video for local playback Audio codec Advanced Audio Coding (AAC) compression has a standard profile known as Low Complexity, or LCAAC. As the name suggests it is a computationally cheap form of compression, requiring little processor time. Originally designed for the MPEG-2 format as a more efficient replacement for MP3, it offers higher sound quality than MP3 compression at the same bit rate. AAC also offers a second profile called High Efficiency, HE-AAC, or AAC+, that further impro
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Formatting video for local playback {*}Recommended video and audio stream parameters{*} Recommended audio codecs, bitrates, and parameters The table below shows suggested values when encoding video and audio streams for local playback on Sony Ericsson phonesThe basic video parameters will offer basic quality upon playback. Conversely the optimal parameters will give truly excellent quality on Sony Ericsson phones, with fluid motion, rich details, and minimal compression artefacts. W810, W800, W
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Formatting video for local playback Using parameters somewhere between the basic and optimal values can be practical when the file size of multimedia content is a concern. Bit rate values can be used to control file size. When reducing bit rate by a large extent it is also advised to scale the frame rate or sample rate of the data stream in proportion, to prevent introducing excessive compression artefacts. {*}The process of formatting multimedia video{*} Typically, there are four stages involve
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Formatting video for local playback Mobile phones have limited audio amplification power, so it is useful to make the audio stream as loud as possible, without compressing dynamic range. This can be done through a technique known as peak normalisation, which will increase the volume of the entire audio stream until the loudest moment is at the absolute maximum volume. Most audio editing software contains this feature, and other tools are also available to achieve it. You may desire to create a s
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Formatting video for local playback Software set-up 1. Install the required software, see "Required software" 2. Select a folder on your computer as a location for saving files, for example, C:\videos. Whatever location you select will be referred to in this document as the working directory. 3. Place a copy of SEexample.avi into the working directory. Creating the video project 1. Open Sony Vegas™ 6.0 and create a new project using the menu File - New.... 2. In the New Project dialog make the f
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Formatting video for local playback 8. In the Properties dialog that appears, check the Normalize option. Click Ok to return to the main window. This will normalise the audio volume level, making the best use of the limited volume on mobile phones. Exporting the formatted video project 1. On the menu select File - Render as... and a new dialog will appear. 2. In the Render As dialog, browse to your working directory, and set the following: • Save as type: Quicktime 6 (*.mov) • File name: SEexamp
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Formatting video for local playback This extends to the exact specifications and practical details of data stream compression and using suitable containers. Optional extra processes and suggestions can be employed to further enrich the level of quality at which the multimedia video content is delivered. Those with no prior experience of editing or formatting digital multimedia video will hopefully find the background information sufficiently enlightening, such that they can understand the more s
